Why is a three phase denoted by R, Y, B ?

Why is a three phase denoted by R, Y, B ?
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Answer :

RYB simply stands for Red, yellow and Blue respectively in a three phase electrical system. In a three phase electrical system, the three phases are separated by an angle of 120 degrees and each phase is given a specific color, i.e. R,Y and B for the phases to be identified.
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Answer :

phase 1 ,R =Red colour cable terminal, phase 2 Y=Yellow colour terminal cable,Phase 3 B=Blue colour cable terminal, N =Neutral. For identification.
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